Between 1973 and 1992, the Mercedes OM616, a 2.4-liter in-line diesel engine, was manufactured. It was fitted to mid-size models like the W115 and W123 as well as the Gellwagen SUV. There are two versions of this power unit because it underwent a significant upgrade in 1978.
OM616, OM601, OM604, OM611, OM640, OM646, OM651, OM654, and OM668 are among the diesel R4-family.
The 1.9-liter OM621 engine, which debuted in 1958, was the forerunner of the 4-cylinder diesel series. A more recent OM615 series power unit with a capacity of 2.0 and 2.2 liters took its place in 1968. The OM616 line’s 2.4-liter engine finally made its debut in 1973. This atmospheric vortex-chamber diesel engine’s design, which included an in-line Bosch M high-pressure fuel pump, a cast-iron cylinder block with liners, a cast-iron 8-valve cylinder head without hydraulic lifters, and a double-row timing chain that rotates a single camshaft, was considered classic at the time.
This power unit served as the foundation for the creation of the OM617 series’ five-cylinder engine in 1974.
Specifications
| Production years | 1973-1992 |
| Displacement, cc | 2404 (sample 1973) 2399 (sample 1978) |
| Fuel system | vortex chamber |
| Power output, hp | 65 (sample 1973) 72 – 75 (sample 1978) |
| Torque output, Nm | 137 |
| Cylinder block | cast iron R4 |
| Block head | cast iron 8v |
| Cylinder bore, mm | 91 (sample 1973) 90.9 (sample 1978) |
| Piston stroke, mm | 92.4 |
| Compression ratio | 21.0 (sample 1973) 21.5 (sample 1978) |
| Hydraulic lifters | no |
| Timing drive | double-row chain |
| Turbocharging | no |
| Recommended engine oil | 10W-40, MB 228.1/229.1 |
| Engine oil capacity, liter | 6.5 |
| Fuel type | diesel |
| Euro standards | EURO 0 |
| Fuel consumption, L/100 km (for Mercedes E 240 D 1985) — city — highway — combined |
9.9 7.2 8.9 |
| Engine lifespan, km | ~800 000 |
| Weight, kg | 225 |
The engine was installed on:
- Mercedes E-Class W115 in 1973 – 1976; E-Class W123 in 1976 – 1986;
- Mercedes G-Class W460 in 1979 – 1987;
- Mercedes MB100 W631 in 1988 – 1992;
- Mercedes T1-Series W601 in 1982 – 1988; T2-Series W602 in 1986 – 1989.
Disadvantages of the OM616 engine
The most well-known flaw in this incredibly durable and dependable diesel engine is the rear crankshaft seal, or packing, which frequently leaks and can result in oil starvation and costly repairs.
The rack drive membrane at Bosch M injection pumps with vacuum control frequently breaks, but this issue is no longer present in the updated MW and M/RSF series pumps. Additionally, the booster pump may unexpectedly fail due to seal wear.
Even though the motor has a double-row timing chain, its lifespan is short. They alter it roughly every 200–250 thousand kilometers, frequently in conjunction with dampers and stars.